Stimulation of tyrosine phosphorylation and accumulation of GTP-bound p21ras upon antibody-mediated alpha 2 beta 1 integrin activation in T-lymphoblastic cells

Integrins are a family of heterodimeric integral plasma membrane proteins that behave as receptors for components of the extracellular matrix and also mediate cell to cell adhesion. Occupation of integrins can result in the transduction of intracellular signals, leading to cytoskeletal reorganization, tyrosine phosphorylation, and induction of gene expression. We report here that the ligation of alpha 2 beta 1 integrin by collagen-adhesion stimulatory anti-alpha 2 and anti-beta 1 antibodies resulted in the accumulation of p21ras in the active GTP-bound state in Jurkat T-lymphoblastoid cells. The activation was accompanied by the tyrosine phosphorylation of proteins of 47-52 kDa. This stimulation of tyrosine phosphorylation and p21ras activation was specific for the activating antibodies and occurred within 2 min of the addition of these antibodies. Although treatment of the cells with the protein kinase C activator, phorbol 12-myristate 13-acetate also resulted in an induction of both cell attachment to collagen and of p21ras activation, tyrosine phosphorylation was not observed. These results demonstrate that alpha 2 beta 1 integrin activation can result in the specific stimulation of tyrosine phosphorylation of 47-52-kDa proteins, as well as activation of a signaling pathway involving p21ras.

Comparison of the clinical efficacy and tolerance of gentamicin PMMA beads on surgical wire versus combined and systemic therapy for osteomyelitis

These data do not prove a statistical superiority of conventional antibiotics or Septopal in the treatment of chronic osteomyelitis. This result, however, is complicated by the biased data set represented by the combined treatment. The data do suggest that cost of treatment is considerably less in patients who are treated with local antibiotics (i.e., Septopal) alone. The rate of adverse experiences was directly related to the use of parenteral antibiotics, with higher rates of adverse experiences in the conventional and combined treatment groups. Furthermore, the Cierny-Mader Physiologic Class had the best correlation with outcome, suggesting that host factors are probably of critical importance in inducing remission of chronic osteomyelitis. This protocol was not designed to test the role of debridement in the treatment of osteomyelitis: it was assumed that debridement would be the same in both groups. It is the investigators' strong opinion, however, that adequacy of debridement was an important determinant in quiescence or recurrence in the study patients. Similarly, there was no strict control for adequacy of soft-tissue coverage provided by local or distant tissue transfer. Again, the investigators believe that adequacy, including viability and durability, of soft-tissue covering was an important determinant for the end result in these patients. Other covariants such as smoking, history, nutritional status, and other measures of general health will be added to this model when data are available. This analysis will allow definition of the appropriate clinical situations in which use of Septopal alone or combined with parenteral antibiotic is indicated.

Septopal beads and autogenous bone grafting for bone defects in patients with chronic osteomyelitis

Thirty-five patients with chronic osteomyelitis were treated with autogenous bone grafts for bone defects. Of 35 patients, two were lost to follow-up evaluation. There were 27 men and six women. The age range was from 18 to 62 years (median age, 29 years). The bones included 22 tibias, nine femurs, and two ulnas. The size of the bone defects ranged from 2.5 x 15 cm (median defect, 2.5 x 6 cm). The length of infection ranged from two to 540 months (median, 31 months). Twenty patients had nonunions and 19 patients required soft-tissue muscle transfers. Patients were treated with systemic antibiotics and/or gentamicin (Septopal) antibiotic beads. Twelve patients were treated with Septopal beads. The range of follow-up evaluation was 24 to 68 months (median, 47 months). Thirty-one of 33 patients had one bone-graft procedure and two patients required two. The time from initial debridement and infection control to bone graft for patients not requiring soft-tissue muscle flaps was one to six weeks (median time, four weeks). For patients requiring soft-tissue muscle transfer, the range was six to nine weeks (median, six weeks). The median time to bone-graft incorporation was six months. All fractures united. Complications included two refractures from auto accidents in the immediate postoperative period, one partial muscle loss, one skin-graft loss, four pin tract draining sites, and two antibiotic-related skin rashes. There was one recurrent infection, and the infection arrest rate was 97%.(ABSTRACT TRUNCATED AT 250 WORDS)

Treatment of chronic osteomyelitis with muscle flaps

This article discusses a study of 36 patients with chronic osteomyelitis that had local or free muscle flaps. Reconstruction of chronic osteomyelitis requires infection control and assessment of soft tissue and bone. In patients with osteomyelitis with an ununited fracture or nonunion, stabilization of the fracture is needed.

Urinary immunoreactive interleukin-1 alpha and interleukin-6 in bacteriuric institutionalized elderly subjects

Urinary immunoreactive interleukin-1 alpha and interleukin-6 levels were measured in specimens obtained from elderly institutionalized subjects, including 67 asymptomatic subjects (51 of whom were bacteriuric), 34 with fever from nonurinary sources, 15 with bacteriuria and 9 with symptomatic urinary infection. For bacteriuric subjects urinary interleukin-1 alpha and interleukin-6 levels were measurable in 18 (35%) and 22 (43%) asymptomatic subjects, respectively, 9 (60%) and 8 (53%) with nonurinary sources of fever, respectively, and 6 (67%) and 7 (78%) with urinary infection, respectively. For subjects without bacteriuria 1 of 16 (6.3%) who were asymptomatic and 5 (25%) with nonurinary sources of fever had measurable urinary interleukin-1 alpha, and 2 (13%) and 1 (5.3%), respectively, had measurable interleukin-6. Presence of interleukin-1 alpha or interleukin-6 was significantly associated with bacteriuria for asymptomatic and symptomatic subjects. Interleukin-1 alpha or interleukin-6 quantitative levels were lower in subjects without than with bacteriuria. Quantitative levels of interleukin-6 tended to decrease for bacteriuric subjects with symptomatic infection between acute and convalescent specimens. These observations suggest that interleukin-1 alpha and interleukin-6 are produced in association with bacteriuria in some elderly subjects. Variation in local cytokine production with time and the clinical significance of these observations require further study.

Unrecognized cocaine use among schizophrenic patients

OBJECTIVE

Unrecognized stimulant use could lead to the misdiagnosis of schizophrenia or the misunderstanding of its course and prognosis. This study was conducted to determine the prevalence of unrecognized stimulant use among patients with a clinical diagnosis of schizophrenia.

METHOD

The subjects were 108 schizophrenic patients admitted consecutively to a Veterans Affairs psychiatric hospital. Admitting psychiatrists supplemented routine clinical evaluations with a semistructured interview regarding recent and lifetime use of alcohol, cocaine, amphetamine, marijuana, and opiates. A urine specimen was assayed for the four illicit drugs.

RESULTS

Of the 103 patients who provided a urine specimen, 37 (36%) used cocaine during the 6 months before admission, including 31 who used the drug in the week before admission. Because of the poor reliability of negative self-reports of recent cocaine use, clinicians failed to recognize cocaine use in one-third of the patients with a urine toxicology positive for cocaine metabolites. Two other groups of patients were identified; schizophrenic patients without substance abuse (including alcohol) and schizophrenic patients with substance abuse other than stimulants. Both substance-abusing groups were younger than the nonabusing group, but the three groups had similarly high rates of recent psychotic symptoms, homelessness, and unemployment.

CONCLUSIONS

Among schizophrenic patients who require hospitalization, clinicians should not rely solely on self-reported stimulant use. Recognition of stimulant use could be improved through routine urine toxicologies for all psychotic patients. The authors suggest that recognition of stimulant use among schizophrenic patients may identify a population with a better prognosis for schizophrenia and different treatment needs.

Beta 1 (CD29) integrin expression in rheumatoid synovial membranes: an immunohistologic study of distribution patterns

Cellular attachment to, and migration into, tissues are critical aspects of the inflammatory process. Our studies were undertaken to examine the distribution of one of the families of adhesion molecules, the beta 1 integrins (VLA antigens), in inflamed rheumatoid synovial tissues. The distribution of lymphocyte subsets and the beta 1 integrins (beta 1, VLA-1, 2, 3, 4, 5) were studied in 10 rheumatoid synovial membranes using immunohistochemistry and monoclonal antibodies. The majority of lymphocytes stained positively for beta 1, VLA-3, VLA-4 and VLA-5. Intravascular mononuclear cells adherent to the endothelium appeared to generally express low levels of beta 1 when compared to those in the extravascular space, suggesting that lymphocytes may augment their expression of this molecule subsequent to their extravasation into the tissue. Cells in the synovial lining layer expressed beta 1, VLA-1, VLA-3 and and VLA-5. The endothelium of the synovial vasculature stained intensely for beta 1, VLA-1, VLA-3 and VLA-5 with more limited staining for VLA-2. The venules and capillaries in and around the subsynovial lymphocytic aggregates demonstrated the most intense vascular staining. We conclude that the beta 1 integrins are expressed by a variety of cells in the rheumatoid synovial membrane. The expression of beta 1 integrins may be subject to regulation by the inflammatory microenvironment thus contributing to a more adhesive environment into which inflammatory cells are more readily recruited and retained.

Lymphocyte-synovial cell interactions: a role for beta 1 and beta 3 integrin-mediated adhesion to cellular fibronectin

The interactions of lymphocytes with cultured synovial cells derived from rheumatoid arthritis patients were examined. A number of lymphoid cell lines bound to these cells. The adherence of several of these lines was inhibited by antibodies to fibronectin. The adherence of the T cell leukemia Jurkat was sensitive to inhibition by antibodies to the fibronectin receptors alpha 4 beta 1 and alpha 5 beta 1. The adherence of the beta 1 integrin negative B cell line RPMI 8866 was inhibited by antibodies to the vitronectin receptor, alpha v beta 3. The interactions of several other cell lines with synovial cells appeared to be independent of this fibronectin-dependent pathway. These results indicate that multiple potential adhesion pathways for cellular interactions in the tissues may exist. The adherence to cell-associated fibronectin may play a contributory role in such processes for certain lymphocyte subsets.

The interactions of gamma delta T cells with extracellular matrix: receptor expression and utilization patterns

Purified populations and clones of human gamma delta T cells were examined for their ability to interact with extracellular matrix (ECM) components. The stimulation of these cells with phorbol ester induced cellular adhesion for ECM. The adhesion structures for fibronectin and collagen were shown to be members of the CD29 integrin family. The expression patterns of beta 1, beta 2 and beta 3 integrins by these cells were examined. The receptor expression and utilization patterns suggest that alpha beta, gamma delta T cells and B cells have similar repertoires of adhesion structure.

Lipoperoxides in sebum of substance users and controls

Sebum was collected from forehead skin in five compulsive heroin and/or cocaine (substance) users and in five controls over three consecutive periods, each lasting three hours. The participants were adult black and white men similar in age and smoking habits, who did not consume alcohol. Lipoperoxides were determined in sebum as malondialdehyde by high performance liquid chromatography. Two participants were excluded in the control group: in both, urinary lipoperoxides were elevated; in one, urine tested positive for delta-9 tetrahydrocannabinol (THC). All other participants had negative urine drug screening tests. Relative to the controls, all substance users had elevated concentrations of lipoperoxides in urine. Compared to the controls, the rate of sebum excretion in the last collecting period was higher in substance users, but sebum had significantly lower lipoperoxide concentration. It is assumed that compulsive drug use may influence lipoperoxidation of incipient sebum, possibly by altered tissue perfusion.

Oculocutaneous manifestations of the erythema multiforme/Stevens-Johnson syndrome/toxic epidermal necrolysis spectrum

Although they were once believed to be distinct diseases, many observers currently consider erythema multiforme, Stevens-Johnson syndrome, and toxic epidermal necrolysis to represent a mild-to-severe continuum of the same process. Each shares certain clinical, histologic, and etiologic characteristics; among the latter two are frequent ocular involvement. Because long-term ophthalmic sequelae may be catastrophic, early recognition and therapy of this acute oculocutaneous disease spectrum are critically important.

Antibodies to different members of the beta 1 (CD29) integrins induce homotypic and heterotypic cellular aggregation

Members of the beta 1 (CD29) integrin family are involved in cellular adhesion to extracellular matrix. However, there have been several reports of CD29 integrin participation in intercellular adhesion. For example, the treatment of the human T cell line Jurkat with antibodies to alpha 4 (CD49d) causes homotypic aggregation. The present report describes the induction of aggregation of Jurkat cells by antibodies to alpha 5 (CD49e) and to a lesser extent by antibodies to the common beta 1/CD29 chain of these integrins. The metabolic requirements for these aggregations are compared with that of the CD49d-induced process. The possible involvement of fibronectin in the cytoadhesion appears to be unlikely as (1) the aggregates form in the absence of plasma fibronectin; (2) antibodies to fibronectin do not inhibit the cell adhesion; and (3) exogenous fibronectin does not influence the process. One of the cognate partners involved in the CD49e-induced aggregation appears to be present on non-antibody-treated Jurkat cells as the cells are coincorporated into aggregates of anti-CD49e-stimulated cells. The adhesion does not appear to involve members of the CD2, CD3, CD4, or CD18 receptor groups. These results indicate that interaction with alpha 4, alpha 5 chain or the beta 1 chain of the CD29 integrins leads to the induction of intercellular adhesion. The possible biological significance of this process is discussed.

Choice and duration of antibiotics in open fractures

Open fracture wounds are contaminated wounds, and wide spectrum antibiotic therapy effective against both gram-positive and gram-negative organisms is recommended. Combination therapy has been shown to be effective in significantly reducing the infection rate in open fractures. For type I and II open fracture wounds, 3 days of antimicrobial therapy is recommended; for type III open fracture wounds, 5 days of treatment is recommended. When secondary procedures are performed, such as bone grafting, open reduction and internal fixation, soft tissue transfers, and other procedures involving the fracture site, an additional 72 hours of therapy is recommended. When antibiotic therapy is given after the initial period, antimicrobials administered should be selected on the basis of the culture and sensitivities of the original infecting organisms.

A silicone pellet for continuous cocaine: comparison with continuous amphetamine

An inexpensive silicone pellet is described for the continuous administration of cocaine for up to 5 days. Rats implanted with this pellet show minimal skin irritation and go through distinct behavioral stages, with an initial period of hyperactivity followed by motor stereotypies. Then, at 3-4 days after implantation, a variety of hallucinogen-like ("late-stage") behaviors appear, including limb flicks, sudden startle responses, and repetitive mid-air grasping movements. Compared to continuous d-amphetamine, continuous cocaine induces decreased motor stereotypies but heightened "late-stage" behaviors.

Analysis of 61 cases of vertebral osteomyelitis

Sixty-one cases of bacterial vertebral osteomyelitis from July 1969 to July 1979 were analyzed. The ages of the 49 men and 12 women ranged from 21 to 66 years. The portal of entry was hematogenous in 58 cases, gunshot wounds in two cases, and and adjacent retroperitoneal abscess in one case. Biopsy was performed in 60 patients. There were 15 complications related to the disease. Gram-negative rods were the predominant bacteria isolated. Blood culture was positive in 13 of the 26 (50%) patients tested. Eleven of the 13 (85%) organisms isolated from the blood cultures correlated with organisms recovered from biopsy specimens. Eleven of the patients had more than one disk level involved. Of the 61 patients, 29 went on to spontaneous fusion, 17 were lost to follow-up study, 11 failed to fuse, three had surgical fusion, and one patient died. Recommendations for diagnosis included the collection of blood cultures and radionuclide bone scans. Management recommendations included systemic antibiotics for at least three weeks and immobilization with either bed rest or spinal orthoses. Surgery was indicated if an abscess was present, neurologic complications occurred, instability became a factor, or the medical treatment failed.

Gunshot injuries to the hip and abdomen: the association of joint and intra-abdominal visceral injuries

A retrospective review of all gunshot injuries to the hip at our medical center over a 24-year period was performed. Adequate information and radiographs were available for 49 patients. Of these, five patients (10.2%) had associated abdominal visceral injuries. These five patients were examined at an average of 5.9 years after their injury, and compared by utilizing the Harris Hip Score rating. Radiographs were also obtained. Four of these five patients (80%) had initially developed infections in their hip joints, with all four having poor functional outcomes, with an average Harris Hip Score of 48.5 from their hip injury. Careful initial evaluation and aggressive surgical and antibiotic treatment are recommended to prevent these poor results.

Cefmetazole and cefonicid. Comparative efficacy and safety in preventing postoperative infections after vaginal and abdominal hysterectomy

A single 1-g dose of cefmetazole was compared with a single 1-g dose of cefonicid for prophylaxis in vaginal and abdominal hysterectomy to determine their efficacy and safety. The antibiotics were administered intramuscularly 15-90 minutes before the incision was made. Cefmetazole and cefonicid had similar activity against most of the aerobic organisms recovered, but cefmetazole was significantly more active against anaerobic gram-negative microorganisms. The patterns of regrowth of vaginal flora were similar in the two treatment groups. Patient demographic characteristics and surgical procedures were similar in both groups. The difference in primary prophylactic failure (e.g., cuff cellulitis) with the two study drugs (1 of 53 [1.9%] with cefmetazole and 2 of 28 [7.1%] with cefonicid) did not reach statistical significance, and the results were similar for the two routes of hysterectomy. Cefmetazole, at a dose of 1 g intramuscularly preoperatively, is a safe and effective agent for prophylaxis during hysterectomy.

Cloning of a gene that encodes a new member of the human cytotoxic cell protease family

A family of unusual serine proteases that are believed to be involved in the effector mechanism of cell-mediated cytotoxicity have previously been described in the mouse. However, in the human only one gene encoding a member has been isolated. By use of a mixture of murine cDNAs as probes, a second human gene has now been isolated. The primary structures of the gene and the predicted protein are very similar to those of the mouse. In addition, in keeping with the postulated involvement in cytolysis, transcripts were detected only in cytotoxic cells. The organization of the coding and noncoding regions of the gene, the clustering of family members, and the chromosomal location, close to the alpha chain of the T cell antigen receptor, are all conserved between human and mouse.

Peripheral teflon catheters. Potential source for bacterial contamination of orthopedic implants?

To detect low numbers of bacterial cells on Teflon catheters removed from peripheral veins, 74 catheter tips were incubated in thioglycollate media for up to ten days. Fifteen (20.3%) of the catheters were found to be culture-positive. Propionibacterium acnes was isolated from seven, Staphylococcus epidermidis from six, and Staphylococcus haemolyticus and Staphylococcus hominis from one each, all common skin organisms associated with infection of implants. An increase in documentation of bacterial contamination resulted from incubating greater than 72 hours; this allowed the slower-replicating Propionibacterium acnes to grow to detectable numbers. Because of these findings and those of others, attention is focused on the peripheral vein conduit as a potential source for hematogenous seeding of implants with bacterial cells. Changing peripheral catheters within 24 hours is recommended to reduce the constant risk of occult bacteremia.

Factors influencing infection rate in open fracture wounds

Seventy-seven infections in 1104 open fracture wounds were evaluated to identify those factors that predisposed to infection. Factors could be placed into three categories: (1) increased risk, (2) no effect, and (3) inconclusive. The single most important factor in reducing the infection rate was the early administration of antibiotics that provide antibacterial activity against both gram-positive and gram-negative microorganisms. In this study, surgical debridement was performed on all open fracture wounds.

Wound site as a predictor of complications following deep nail punctures to the foot

The site of injury, condition of the nail, and type of foot covering were compared in 36 inpatients and 34 outpatients with nail puncture wounds to the foot. Of the 36 inpatients, 34 (94%) had pyarthrosis, osteomyelitis, or both. The plantar surface of the foot was divided into 3 zones. Of the 36 inpatients, 35 (97%) had deep puncture wounds in zone 1. In contrast, only 6 of 34 (18%) outpatients had injury to this area. Tennis shoes were shown to predispose to infection with Pseudomonas aeruginosa. Based on our findings, an early hospital admission should be considered for all patients with deep puncture wounds located in zone 1 and for patients who give a history of bone penetration in zone 2 or 3 at the time of injury. All patients who meet the above criteria and who are not admitted to hospital should be observed closely.

Comparative efficacy and safety of cefmetazole or cefoxitin in the prevention of postoperative infection following vaginal and abdominal hysterectomy

We evaluated three 1-g doses of cefmetazole in comparison with the standard three 2-g doses of cefoxitin for prophylaxis in vaginal or abdominal hysterectomy to determine efficacy and safety. The antibiotics were administered intravenously 30-90 min before the incision and were followed with additional intravenous doses 8 and 16 h or 6 and 12 h later, respectively. The patients received povidone-iodine vaginal preparations before surgery; vaginal packs, when used, contained no antibiotic agents. Vaginal cultures were obtained before the vaginal preparation, at the time of discharge from hospital and when there was a suggestion of operative site infection. The activity of both antibiotics against these organisms was tested. Patient demographic characteristics and surgical procedures were similar in each treatment group. The difference between the primary failure rates with the two antibiotics (2 of 35 (5.7%) with cefmetazole and 2 of 16 (12.5%) with cefoxitin) did not reach statistical significance, and results were similar for the two routes of hysterectomy. Cefmetazole was more active than cefoxitin against the majority of the aerobic and anaerobic organisms recovered, although approximately 20-30% of the isolates showed resistance, or intermediate sensitivity, generally to both antibiotics.

The use of adaptive algorithms for obtaining optimal electrical shimming in magnetic resonance imaging (MRI)

A method of determining the dc coil current values to electrically shim the static magnetic fields used in magnetic resonance imaging (MRI) using modified steepest descent adaptive algorithm is described. Using a 32 cm diameter by a 40 cm long water phantom as the test volume, the algorithm achieved field homogeneities of 0.2 parts per million (ppm) peak-to-peak within a 20 cm diameter spherical imaging volume, and 1.3 ppm peak-to-peak within the entire phantom. The algorithm achieved an inhomogeneity variance of 0.18 ppm2. The shim system was successfully modeled as a sum of adaptive linear combiners. The model contains 13 parameters that can be varied, 12 shim coil currents, and the receiver mixer frequency. The model was then used to predict key adaptive algorithm parameters. Experimental verification of these parameters lends support to the accuracy of the model.